The Waldenecksee or Petersee is a quarry lake on the western edge of the Northern Black Forest. It lies in an exclave of the municipality of Sinzheim, surrounded by Baden-Baden, between Iberg and Fremersberg on the western side of the hill of Waldeneck. Around 1900 a quarry was established here that was worked until 1968. After that a lake formed on the floor of the quarry, about 200 metres long and 35–75 metres wide. One of its common names, the Petersee, is derived from the name of the former quarry owners, the Peter Porphyry Gravel Works (Porphyr-Schotterwerk Peter). Today it is leased as a
The Waldenecksee or Petersee is a quarry lake on the western edge of the Northern Black Forest. It lies in an exclave of the municipality of Sinzheim, surrounded by Baden-Baden, between Iberg and Fremersberg on the western side of the hill of Waldeneck. Around 1900 a quarry was established here that was worked until 1968. After that a lake formed on the floor of the quarry, about 200 metres long and 35–75 metres wide. One of its common names, the Petersee, is derived from the name of the former quarry owners, the Peter Porphyry Gravel Works (Porphyr-Schotterwerk Peter). Today it is leased as an angling lake and bathing is forbidden.
== Ecology == Because water could not circulate in the lake as it is fed by springs and surface water, and because of nutrients introduced by plant growth and bathers, there was a risk of life in the lake dying out. This could only be prevented in summer 2013 by the intervention of the fire service who enriched the lake water by spraying it with oxygen. thumb|left|Solar-driven circulator pump Thereafter the leaseholders of the lake, Sinzheim Sports Fishing Club, with financial support from the municipality of Sinzheim 2014, installed a solar-powered circulator pump, which pumps water from the lakebed to the surface.
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